Takes an image and greyscales it.
npm install greyscaler
###CLI Usage: greyscaler [options]
Options:
-h, --help output usage information
-V, --version output the version number
-i, --images <images> Images to greyscale
-o, --outputPath [outputPath] Output path
###Module var greyscaler = require('./greyscaler');
greyscaler('test.png', './output', callback);